scholarly journals Different Types of Periampullary Duodenal Diverticula Are Associated with Occurrence and Recurrence of Bile Duct Stones: A Case-Control Study from a Chinese Center

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Zhen Sun ◽  
Wenhui Bo ◽  
Ping Jiang ◽  
Quan Sun
Keyword(s):  
Acute Pancreatitis ◽  
Bile Duct ◽  
Control Group ◽  
Successful Cannulation ◽  
Cbd Stones ◽  
Duodenal Diverticula ◽  
Different Types ◽  
Type 3

Aims. We here investigated the association of different types of periampullary diverticula (PAD) with pancreaticobiliary disease and with technical success of endoscopic retrograde cholangiopancreatography (ERCP).Methods. A total of 850 consecutive patients who underwent their first ERCP were entered into a database. Of these patients, 161 patients (18.9%) had PAD and the age- and sex-matched control group comprised 483 patients.Results. PAD was correlated with common bile duct (CBD) stones (59.6% versus 35.0% in controls;P=0.008) and negatively correlated with periampullary malignancy (6.8% versus 21.5% in controls;P=0.004). The acute pancreatitis was more frequent (62.5%) in patients with PAD type 1 followed by PAD type 2 (28.9%,P=0.017) and type 3 (28.0%,P=0.006). No significant differences were observed in successful cannulation rate and post-ERCP complications among the 3 types of PAD. Type 1 PAD patients had less recurrence of CBD stones than did the patients who had type 2 or type 3 PAD (53.8% versus 85.7%;P=0.043).Conclusions. PAD, especially type 1 PAD, is associated with an increased acute pancreatitis as well as occurrence and recurrence of CBD stones. PAD during an ERCP should not be considered as an obstacle to a successful cannulation.

FUNCTIONAL STATUS AND ADAPTIVE POTENTIAL IN FOREIGN STUDENTS WITH DIFFERENT TYPES OF VEGETATIVE REGULATION DURING TUITION

2020 ◽  
pp. 118-126
Author(s):  
A.M. Satarkulova
Keyword(s):  
Heart Rate ◽  
Foreign Students ◽  
Autonomic Regulation ◽  
The Body ◽  
Functional Changes ◽  
Different Types ◽  
Type 3 ◽  
Adaptive Abilities

The assessment and dynamic control over students’ status is a very important task. It allows timely detection of prenosological status prior to pathology and health maintenance in students. The objective of the paper is to assess the adaptive abilities of the body, to analyze changes in heart rate variability indicators in students with various types of autonomic regulation, to identify prenosological status and precursory pathological symptoms. Materials and Methods. The study enrolled 302 students from India, aged 21.54±1.43. Programming complex «Psychophysiologist» was used to register the main HRV parameters within 5 minutes. Health status was evaluated according to the index of functional changes and the scale of functional states. Results. N.I. Shlyk (2009) distinguished two groups of students with different types of autonomic regulation: type 1 (53 %) with moderate and type 2 (5 %) with marked characteristics of central regulation profile, type 3 (35 %) with moderate and type 4 (7 %) with marked characteristics of autonomous regulation profile. Main parameters of HRV and adaptation potential were defined for each student.All the parameters characterized functional and health status. Conclusions. It was shown that 82 % of trial subjects (type 1), 53 % (type 2), 94 % (type 3) and 95 % (type 4) demonstrated satisfactory adaptation and their physiological processes were at an optimal level. 18 % of students (type 1) demonstrated reduced adaptive abilities of the body. Moreover, they were under moderate stress. 47 % of subjects (type 2) were also under a significant stress, which was proven by excessively high SI, low SDNN and TP, and an increased index of functional changes. 5 % of students (type 4) revealed dysfunctional characteristics in the heart rhythm, peculiar to pathology. Keywords: foreign students, heart rate variability, types of autonomic regulation, adaptation potential, functional status. Оценка состояния студентов и динамический контроль за ним является важной задачей, поскольку позволяет своевременно выявлять у студентов донозологические состояния, предшествующие патологии, и способствовать сохранению здоровья. Цель. Оценка адаптивных возможностей организма, анализ изменений показателей вариабельности сердечного ритма у студентов с различными типами вегетативной регуляции, выявление донозологических состояний и ранних признаков патологии. Материалы и методы. В исследовании участвовало 302 студента в возрасте 21,54+1,43 года из Индии. Регистрировались основные параметры ВСР в течение 5 мин с использованием программно-аппаратного комплекса «Психофизиолог». Состояние и уровень здоровья оценивались по индексу функциональных изменений и шкале функциональных состояний. Результаты. По способу, предложенному Н.И. Шлык, выделены группы студентов с различными типами вегетативной регуляции: I (53 %) и II типы (5 %) – с умеренным и выраженным преобладанием центрального контура регуляции соответственно, III (35 %) и IV типы (7 %) – с умеренным и выраженным преобладанием автономного контура регуляции соответственно. У каждого из студентов определены основные параметры ВСР и адаптационного потенциала, характеризующие функциональное состояние и уровень здоровья. Выводы. Показано, что для 82 % обследуемых с I типом, 53 % со II типом, 94 % c III типом и 95 % с IV типом регуляции характерно состояние удовлетворительной адаптации, физиологические процессы сохраняются на оптимальном уровне. В группе студентов I типа у 18 % студентов адаптивные возможности организма снижены, выявлено состояние умеренного напряжения. У 47 % обследуемых II типа также зафиксировано состояние резко выраженного напряжения, индикатором которого является чрезмерно высокое значение SI, низкие величины SDNN и ТP, повышенное значение индекса функциональных изменений. В группе студентов с IV типом у 5 % учащихсяв регуляции ритма сердца выявлены дисфункциональные признаки, характерные для патологии. Ключевые слова: иностранные студенты, вариабельность сердечного ритма, типы вегетативной регуляции, адаптационный потенциал, функциональное состояние.

New Concept: Different Types of Insufficiency of the Saphenofemoral Junction Identified by Duplex as a Chance for a More Differentiated Therapy of the Great Saphenous Vein

2013 ◽  
Vol 28 (5) ◽  
pp. 268-274 ◽  
Author(s):  
M Stücker ◽  
R Moritz ◽  
P Altmeyer ◽  
S Reich-Schupke
Keyword(s):  
Clinical Practice ◽  
Saphenous Vein ◽  
Great Saphenous Vein ◽  
Effective Therapy ◽  
Optimal Therapy ◽  
Different Types ◽  
Type 3 ◽  
Saphenofemoral Junction

Even though the item ‘saphenofemoral junction’ (SFJ) is anatomically well defined, the incontinence of the SFJ is often incompetently described in clinical practice and studies. Especially with regard to the optimal therapy of the great saphenous vein, it might be of importance to have a more distinct regard to the SFJ as it is known that about 10–30% of the saphenous refluxes have no femoral origin. Considering the terminal and preterminal valve three types of incompetence of the SFJ may be differentiated: Type 1: Incompetent terminal, but competent preterminal valve; Type 2: Competent terminal, but incompetent preterminal valve; Type 3: Incompetent terminal and preterminal valve (complete incompetence). A review on prior studies and reports leads to the assumption that the differentiation of the distinct types of SFJ-incompetence allows a more individual and – perhaps – more effective therapy. Finally, studies are necessary to evaluate the here given new concept.

scholarly journals Kappa Free Light Chains and IgG Combined in a Novel Algorithm for the Detection of Multiple Sclerosis

2020 ◽  
Vol 10 (6) ◽  
pp. 324
Author(s):  
Monika Gudowska-Sawczuk ◽  
Joanna Tarasiuk ◽  
Alina Kułakowska ◽  
Jan Kochanowicz ◽  
Barbara Mroczko
Keyword(s):  
Multiple Sclerosis ◽  
Oligoclonal Bands ◽  
Light Chains ◽  
Control Group ◽  
Free Light Chains ◽  
Pattern Type ◽  
Multiple Sclerosis Patients ◽  
Type 3

Background: It is well known that the cerebrospinal fluid (CSF) concentrations of free light chains (FLC) and immunoglobulin G (IgG) are elevated in multiple sclerosis patients (MS). Therefore, in this study we aimed to develop a model based on the concentrations of free light chains and IgG to predict multiple sclerosis. We tried to evaluate the diagnostic usefulness of the novel κIgG index and λIgG index, here presented for the first time, and compare them with the κFLC index and the λFLC index in multiple sclerosis patients. Methods: CSF and serum samples were obtained from 76 subjects who underwent lumbar puncture for diagnostic purposes and, as a result, were divided into two groups: patients with multiple sclerosis (n = 34) and patients with other neurological disorders (control group; n = 42). The samples were analyzed using turbidimetry and isoelectric focusing. The κIgG index, λIgG index, κFLC index, and λFLC index were calculated using specific formulas. Results: The concentrations of CSF κFLC, CSF λFLC, and serum κFLC and the values of κFLC index, λFLC index, and κIgG index were significantly higher in patients with multiple sclerosis compared to controls. CSF κFLC concentration and the values of κFLC index, λFLC index, and κIgG index differed in patients depending on their pattern type of oligoclonal bands. κFLC concentration was significantly higher in patients with pattern type 2 and type 3 in comparison to those with pattern type 1 and type 4. The κFLC index, λFLC index, and κIgG index were significantly higher in patients with pattern type 2 in comparison to those with pattern type 4. The κFLC index and κIgG index were significantly higher in patients with pattern type 2 in comparison to those with pattern type 1, and in patients with pattern type 3 compared to those with pattern type 4. The κIgG index was markedly elevated in patients with pattern type 3 compared to those with pattern type 1. In the total study group, κFLC, λFLC, κFLC index, λFLC index, κIgG index, and λIgG index correlated with each other. The κIgG index showed the highest diagnostic power (area under the curve, AUC) in the detection of multiple sclerosis. The κFLC index and κIgG index showed the highest diagnostic sensitivity, and the κIgG index presented the highest ability to exclude multiple sclerosis. Conclusion: This study provides novel information about the diagnostic significance of four markers combined in the κIgG index. More investigations in larger study groups are needed to confirm that the κIgG index can reflect the intrathecal synthesis of immunoglobulins and may improve the diagnosis of multiple sclerosis.

New insights into the magmatic system southeast of El Hierro from high-resolution 2D seismic data

2020 ◽  
Author(s):  
Kai-Frederik Lenz ◽  
Felix Gross ◽  
Andreas Klügel ◽  
Rachel Barrett ◽  
Philipp Held ◽  
...  
Keyword(s):  
High Resolution ◽  
Canary Islands ◽  
Magmatic Activity ◽  
Magmatic System ◽  
El Hierro ◽  
Specific Distribution ◽  
Different Types ◽  
Type 3

<p>A new high-resolution seismic dataset is used to investigate the distribution and influence of different phases of magmatic activity in the southeast of El Hierro, Canary Islands. The Canary Archipelago off NW-Africa has largely been formed over the past 20 Myr, but older volcanic edifices exist. One of those older edifices is Henry Seamount, an extinct 126 Ma volcano located 40 km southeast of El Hierro, the youngest (1.1 Ma) and westernmost of the Canary Islands. Hence, the area southeast of El Hierro is influenced by both older and younger magmatic activity. We also found evidence for comparatively young volcanic activity at Henry Seamount, probably contemporaneous to El Hierro. Therefore, a complex magmatic system is assumed to have resulted in the different phases of magmatic activity.</p><p>A detailed high-resolution 2D seismic reflection dataset was collected in an area between El Hierro and Henry Seamount during RV Meteor expedition M146 in 2018 to image the expressions of this magmatic system in the upper sub-surface. Several acoustic blanking zones were discovered and identified as the most prominent features in this seismic dataset. We classify these blanking zones into three different types. Type 1 blanking zones are related to volcanic edifices, which crop out at the seafloor and cut through all imaged sedimentary units. Type 2 blanking zones are characterised by upward bending of adjacent reflectors and are most likely caused by hydrothermal doming resulting from saucer-shaped sill intrusions. Type 3 blanking zones cut clearly through adjacent reflectors, and are probably related to fluids or gases that were mobilized by the sill intrusions. The type 1 and 2 blanking zones cluster in the central part of the working area, whereas the blanking zones of type 3 are located on the outskirts. This specific distribution and the occurrence of the varying blanking zone types are combined to make a conceptual model of this complex magmatic system. Our model takes sill intrusions, hydrothermal doming, as well as volcanic out-crops and mobilized fluids into account. Therefore, this study provides new insights into the magmatic evolution of the youngest Canary Island, which can help to achieve a better understanding of the whole system.</p>

Orthotic variations in the management of infantile tibia vara and the results of treatment

2013 ◽  
Vol 37 (5) ◽  
pp. 375-383 ◽  
Author(s):  
Serap Alsancak ◽  
Senem Guner ◽  
Hakan Kinik
Keyword(s):  
Successful Outcome ◽  
Foot Orthoses ◽  
Full Time ◽  
Duration Of Treatment ◽  
Tibia Vara ◽  
Ankle Foot Orthoses ◽  
Different Types ◽  
Type 3

Background:Infantile tibia vara is an acquired form of tibial deformity associated with tibial varus and internal torsion. Several methods have been described for orthotics treatment. The purpose of this study was to determine the effectiveness of orthotics treatment in infantile tibia vara.Study design:Controlled trial.Objective:The aim of this study was to compare the effect of different types of orthoses and correction methods on decreasing the curve in children with severe genu varum.Methods:Three different types of knee–ankle–foot orthoses were applied to 35 lower extremities of 22 pediatric participants who were 19–38 months of age. The same orthotic design principles were used to correct the femur, while different designs were applied to correct the tibia. The orthoses used on 20 participants were evaluated for differences among them and their effects on the treatment process. In addition, methods used in the treatment, problems encountered, production of different types of orthoses, convenience of application of the orthoses, and degree of patients satisfaction are discussed in this article.Results:The mean duration of treatment of the participants until completion of treatment was 25.3 ± 9.7 weeks with a minimum of 9 weeks and a maximum of 41 weeks. No statistically significant correlation was found between the duration of orthotic use in patients with a successful outcome and percentile height and percentile weight. When the duration of treatment using the different types of orthoses was analyzed, significant differences were found between Type 1 and Type 2, and Type 1 and Type 3 orthoses (p < 0.05), while no difference was observed between Type 2 and Type 3 orthoses (p > 0.05).Conclusion:We found that bracing is an effective form of treatment for infantile tibia vara up to 38 months of age. We conclude that full-time use of knee–ankle–foot orthoses exerting corrective forces from five points along the full length of the limb was effective.Clinical relevance:The localization of the distal tibial correction, the quality of the midtibial correction band, and the importance of the application of corrective forces from five points with rigid methods were found.

scholarly journals Types of the statics of the spine in patients of young, elderly and senile age

2020 ◽  
pp. 38-48
Author(s):  
A. M. Orel
Keyword(s):  
Quantitative Assessment ◽  
Qualitative Assessment ◽  
Control Group ◽  
Entire Group ◽  
X Ray ◽  
Qualitative And Quantitative ◽  
Utility Patent ◽  
Type 3

Introduction. A complete and systematic x-ray examination of all parts of the spine at the same time in elderly and senile people has not yet been carried out. On the other hand, radiography can identify spinal statics disorders that are typical for this category of people.The goal of research — describe the types of spinal statics disorders in young, elderly and senile people.Materials and methods. Digital radiography of all parts of the spine was performed in 103 patients with dorsopathies. The first group included 50 patients aged 60–74 years; men 16, women 34. The second study group included 21 patients aged 75–88 years, 6 men and 15 women. The third control group included 32 randomly selected people aged 21 to 45 years, 15 men and 17 women. The study belongs to the group of a posteriori x-ray processing and was carried out without the participation and additional irradiation of patients. On the screen of a personal computer, using the methods developed by the author, unified digital x-ray images of all parts of the spine of each patient were obtained. From the INION point, a vertical line occipital vertical descended along all the structures of the spine. Using the midpoint of the front and rear contour x-ray image of the vertebral body of the TII and TXII the front-rear axes were passed through until they intersect with the occipital vertical at the back and intersect with each other at the front. A qualitative assessment of the occipital vertical passage relative to the structures of the spine and a quantitative assessment of the angles of inclination and the angle of intersection of the front-rear axes of the TII and TXII vertebrae was carried out..Results. Five types (from 0 to 4) of spine statics were described and criteria for their qualitative and quantitative assessment were determined. It was found that in the control group, the most common type of spine statics was zero (0), while type 3 and 4 were not determined. In contrast, 3 and 4 types of spinal statics were most frequently observed in second group of patients. In the first group of patients, types 1 and 2 of spine statics were most often revealed, and other types of spine statics also occurred. Among the entire group of examined patients n=103 0 type of spinal statics disorder was detected in 27 (26,2 %) patients, type 1 in 35 (34 %), type 2 in 22 (21,3 %), type 3 in 11 (10,7 %) and type 4 in 8 patients (7,8 %). In patients with type 0 spinal statics, the angle of inclination of the front-rear axis of the TII vertebra was 16,67±8,49º, and of the TXII vertebra was 18,33±4,33º. In type 1 statics of the spine, the angle of inclination of the front-rear axis of the TII vertebra was 26,66±6,73º, and of the TXII vertebra was 21,17±4,92º. In type 2 spinal statics, the angle of inclination of the front-rear axis of the TII vertebra was 32,95± 6,82º, and of the TXII vertebra was 19,68±5,4º. In type III spinal statics, the angle of inclination of the front-rear axis of the TII vertebra was 41,09±9,22º, and of the TXII vertebra 26±11,05º. Type 4 statics of the spine were diagnosed in the presence of type 1–3 statics, in addition to which a pathological fracture or multiple compression fractures were detected in any part of the spine, or the vertebral bodies took the form of fish vertebrae.Conclusion. The study demonstrated the presence of characteristic prevailing types of spinal statics in young, elderly and senile people. These qualitative and quantitative criteria allow us to evaluate them. Based on the results of the study, an application for the utility patent of the Russian Federation «The Method for Evaluating Spine Statics», № 2019144992, priority dated 30.12.2019 was issued and filed. The identified qualitative and quantitative indicators can be used to develop criteria for determining the biological age of a person, which will contribute to improving the evidence-based approach to medicine. 

scholarly journals Infestation of parasitic rhizocephalan barnacles Sacculina beauforti (Cirripedia, Rhizocephala) in edible mud crab, Scylla olivacea

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3419 ◽  
Author(s):  
Khor Waiho ◽  
Hanafiah Fazhan ◽  
Henrik Glenner ◽  
Mhd Ikhwanuddin
Keyword(s):  
Mud Crab ◽  
Mitochondrial Coi ◽  
Normal Individuals ◽  
Different Types ◽  
Rhizocephalan Barnacles ◽  
Commercially Important ◽  
The Mean ◽  
Type 3

Screening of mud crab genus Scylla was conducted in four locations (Marudu Bay, Lundu, Taiping, Setiu) representing Malaysia. Scylla olivacea with abnormal primary and secondary sexual characters were prevalent (approximately 42.27% of the local screened S. olivacea population) in Marudu Bay, Sabah. A total of six different types of abnormalities were described. Crabs with type 1 and type 3 were immature males, type 2 and type 4 were mature males, type 5 were immature females and type 6 were mature females. The abdomen of all crabs with abnormalities were dented on both sides along the abdomen’s middle line. Abnormal crabs showed significant variation in their size, weight, abdomen width and/or gonopod or pleopod length compared to normal individuals. The mean body weight of abnormal crabs (type 1–5) were higher than normal crabs with smaller body size, while females with type 6 abnormality were always heavier than the normal counterparts at any given size. Sacculinid’s externa were observed in the abdomen of crabs with type 4 and type 6 abnormalities. The presence of embryos within the externa and subsequent molecular analysis of partial mitochondrial COI region confirmed the rhizocephalan parasite as Sacculina beauforti. Future in-depth descriptions of the life cycle and characteristics of S. beauforti are recommended as it involves a commercially important edible crab species and the effect on human health from the consumption of crabs is of crucial concern.

Cavum Septi Pellucidi in Boxers

2010 ◽  
Vol 61 (1) ◽  
pp. 29-32 ◽  
Author(s):  
Richard I. Aviv ◽  
George Tomlinson ◽  
Brian Kendall ◽  
Chandrashekhar Thakkar ◽  
Alan Valentine
Keyword(s):  
Control Group ◽  
Resonance Imaging ◽  
Cavum Septi Pellucidi ◽  
Mri Studies ◽  
Magnetic Resonance Imaging Mri ◽  
License Renewal ◽  
Type 3 ◽  
Parenchymal Abnormalities

Objective Controversy exists over the significance of the isolated finding of cavum septi pellucidi (CSP) and its prevalence rate in healthy individuals and in professional boxers. Few magnetic resonance imaging (MRI) studies have looked at large cohorts of boxers. The aim of this study was to identify the prevalence and extent of a CSP among professional boxers and to compare these with a control group. Methods MRI studies of 164 male boxers scanned for annual British boxing board license renewal were reviewed and compared with 43 control patients. CSP prevalence, size, and extent were recorded. Extent was classified as type 1, anterior to the fornix; type 2, extending up to the fornix; and type 3, extending into the cavum vergae. Parenchymal abnormalities were documented, and the Evan's ratio was used as an indication of brain atrophy. Results A CSP was present in 40% of controls and 49% of boxers. There was a trend to a higher CSP prevalence in boxers ( P = .099). No control patient had type 2 or 3 extension ( P < .0009), as opposed to 30% and 16% prevalence in boxers. Three boxers increased their extent over serial imaging. No difference in CSP size was established between the 2 groups ( P = .43), but there was an association between progressive scans and increased CSP size over time in boxers, independent of age ( P = .05). Eight boxers demonstrated a CSP on a subsequent scan not seen on an earlier scan. Conclusion The prevalence of a CSP is high among both control patients and boxers. There is a trend to a larger CSP with increasing number of scans without evidence of atrophy and independent of age. Boxers also have a greater posterior extent than controls. The findings may be explained by sudden increases in intracranial pressure that forced cerebrospinal fluid (CSF) through small defects in the septal leaflets, which result in an increase in size and or extent of a CSP.

scholarly journals Morphometry and Morphology of Rouviere’s Sulcus of Liver for Laparoscopic Cholecystectomy - A Cadaveric Study

2021 ◽  
Vol 10 (19) ◽  
pp. 1403-1407
Author(s):  
Deepali D. Deshatty ◽  
Shruthi B.N. ◽  
Kavitha S ◽  
Merlyn Madhumitha L
Keyword(s):  
Laparoscopic Cholecystectomy ◽  
Bile Duct ◽  
Observational Study ◽  
Key Words ◽  
Bile Duct Injury ◽  
Average Length ◽  
Inferior Surface ◽  
Type 3

BACKGROUND The Rouviere’s sulcus (RS) is a horizontal sulcus on inferior surface of liver. The identification of RS may avoid bile duct injury during laparoscopic cholecystectomy and reduce the number of complications. RS is useful but often ignored anatomic landmark. The purpose of the study was to determine the presence/absence, types, and morphometry of demonstrable Rouviere’s sulcus. METHODS This observational study was conducted on 50 (cadaveric) liver specimens obtained during dissection. All the surfaces were meticulously observed, the RS was identified and photographed. The parameters like its presence/ absence, type of sulcus, length, breadth and depth were measured. Later it is classified into type 1, 2 & 3 depending on its morphology. RESULTS The Rouviere’s sulcus was present in 36 (72 %) specimens. The type 1RS in 29 (58 %), type 2 RS in 4 (8 %) and type 3 RS in 3 (6 %) specimens was observed. The RS was horizontal in 25 (50 %) specimens and oblique in 11 (22 %) specimens. The average length, breadth and depth of RS were 3.5 cm, 0.14 cm & 0.52 cm respectively. CONCLUSIONS The knowledge of presence / absence of Rouviere’s sulcus, its type and morphometry provide useful information to the surgeons to avoid bile duct injury during laparoscopic cholecystectomy and to achieve a good outcome. KEY Words Rouviere’s Sulcus, Laparoscopic Cholecystectomy, Bile Duct Injury

scholarly journals Terminus behavior and response time of North Cascade glaciers, Washington, U.S.A.

2001 ◽  
Vol 47 (158) ◽  
pp. 497-506 ◽  
Author(s):  
Mauri S. Pelto ◽  
Cliff Hedlund
Keyword(s):  
Response Time ◽  
Mass Balance ◽  
Accumulation Rate ◽  
Initial Response ◽  
Ice Age ◽  
Different Types ◽  
Type 3 ◽  
Annual Balance

AbstractObservation of the terminus behavior of 38 North Cascade glaciers, Washington, U.S.A., since 1890 shows three different types of glacier response: (1) Continuous retreat from the Little Ice Age (LIA) advanced positions from 1890 to approximately 1950, followed by a period of advance from 1950 to 1976, and then retreat since 1976. (2) Rapid retreat from 1890 to approximately 1950, slow retreat or equilibrium from 1950 to 1976, and moderate to rapid retreat since 1976. (3) Continuous retreat from 1890 to the present.Type 1 glaciers are notable for steeper slopes, extensive crevassing and higher terminusregion velocities. Type 2 glaciers have intermediate velocities, moderate crevassing and intermediate slopes. Type 3 glaciers have low slopes, modest crevassing and low terminusregion velocities. This indicates that the observed differences in the response time and terminus behavior of North Cascade glaciers in reaction to climate change are related to variations in specific characteristics of the glaciers. The response time is approximately 20–30 years on type 1 glaciers, 40–60 years on type 2 glaciers and a minimum of 60–100 years on type 3 glaciers. The high correlation in annual balance between North Cascade glaciers indicates that microclimates are not the key to differences in behavior. Instead it is the physical characteristics — slope, terminus velocity, thickness and accumulation rate — of the glacier that determine recent terminus behavior and response time. The delay between the onset of a mass-balance change and initiation of a noticeable change in terminus behavior has been observed on 21 glaciers to be 4–16 years. This initial response time applies to both positive and negative changes in mass balance.

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